From f341fbf934364d96e2a1f932190f83b3d33b8adf Mon Sep 17 00:00:00 2001
From: christos <christos@NetBSD.org>
Date: Sun, 8 Mar 2015 22:45:16 +0000
Subject: [PATCH] dtrace bits from riastradh

---
 sys/dev/lockstat.c | 26 ++++++++++++++++++++++++--
 sys/dev/lockstat.h | 16 +++++++++++++++-
 2 files changed, 39 insertions(+), 3 deletions(-)

diff --git a/sys/dev/lockstat.c b/sys/dev/lockstat.c
index 9884fdd8bed9..fb1a8da7ea09 100644
--- a/sys/dev/lockstat.c
+++ b/sys/dev/lockstat.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: lockstat.c,v 1.19 2014/07/25 08:10:35 dholland Exp $	*/
+/*	$NetBSD: lockstat.c,v 1.20 2015/03/08 22:45:16 christos Exp $	*/
 
 /*-
  * Copyright (c) 2006, 2007 The NetBSD Foundation, Inc.
@@ -40,7 +40,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: lockstat.c,v 1.19 2014/07/25 08:10:35 dholland Exp $");
+__KERNEL_RCSID(0, "$NetBSD: lockstat.c,v 1.20 2015/03/08 22:45:16 christos Exp $");
 
 #include <sys/types.h>
 #include <sys/param.h>
@@ -110,6 +110,20 @@ size_t		lockstat_sizeb;
 int		lockstat_busy;
 struct timespec	lockstat_stime;
 
+#ifdef KDTRACE_HOOKS
+CTASSERT(LB_NEVENT <= 3);
+CTASSERT(LB_NLOCK <= (7 << LB_LOCK_SHIFT));
+void
+lockstat_probe_stub(uint32_t id, uintptr_t lock, uintptr_t callsite,
+    uintptr_t flags, uintptr_t count, uintptr_t cycles)
+{
+}
+
+uint32_t	lockstat_probemap[LS_NPROBES];
+void		(*lockstat_probe_func)(uint32_t, uintptr_t, uintptr_t,
+		    uintptr_t, uintptr_t, uintptr_t) = &lockstat_probe_stub;
+#endif
+
 const struct cdevsw lockstat_cdevsw = {
 	.d_open = lockstat_open,
 	.d_close = lockstat_close,
@@ -344,6 +358,14 @@ lockstat_event(uintptr_t lock, uintptr_t callsite, u_int flags, u_int count,
 	u_int event;
 	int s;
 
+#ifdef KDTRACE_HOOKS
+	uint32_t id;
+	CTASSERT((LS_NPROBES & (LS_NPROBES - 1)) == 0);
+	if ((id = lockstat_probemap[LS_COMPRESS(flags)]) != 0)
+		(*lockstat_probe_func)(id, lock, callsite, flags, count,
+		    cycles);
+#endif
+
 	if ((flags & lockstat_enabled) != flags || count == 0)
 		return;
 	if (lock < lockstat_lockstart || lock > lockstat_lockend)
diff --git a/sys/dev/lockstat.h b/sys/dev/lockstat.h
index d3d0e91b3196..ef95d7c05621 100644
--- a/sys/dev/lockstat.h
+++ b/sys/dev/lockstat.h
@@ -1,4 +1,4 @@
-/*	$NetBSD: lockstat.h,v 1.10 2009/01/20 14:49:00 yamt Exp $	*/
+/*	$NetBSD: lockstat.h,v 1.11 2015/03/08 22:45:16 christos Exp $	*/
 
 /*-
  * Copyright (c) 2006 The NetBSD Foundation, Inc.
@@ -33,6 +33,7 @@
 #define _SYS_LOCKSTAT_H_
 
 #ifdef _KERNEL_OPT
+#include "opt_dtrace.h"
 #include <lockstat.h>
 #endif
 
@@ -195,4 +196,17 @@ extern volatile u_int	lockstat_enabled;
 
 #endif
 
+#ifdef KDTRACE_HOOKS
+#define LS_COMPRESS(f) \
+    ((((f) & 3) | (((f) & 7) >> 6)) & (LS_NPROBES - 1))
+#define	LS_NPROBES	0x20	/* 5 bits */
+
+extern uint32_t	lockstat_probemap[];
+extern void	(*lockstat_probe_func)(uint32_t, uintptr_t, uintptr_t,
+    uintptr_t, uintptr_t, uintptr_t);
+
+void		lockstat_probe_stub(uint32_t, uintptr_t, uintptr_t,
+    uintptr_t, uintptr_t, uintptr_t);
+#endif
+
 #endif	/* _SYS_LOCKSTAT_H_ */